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The ion-plated lead lubrication of the Giotto spacecraft despin mechanism was subjected to an accelerated torque test in vacuum on a pair of angular contact 55 mm ID bearings. A first series of 10 million revolutions was extended by 90 million revolutions (although for Giotto a mission life of 4.5 million is expected). Over 100 million revolutions the torque characteristics of the lead lubricated bearings fall well within the limits set. The 16 rpm torque noise (standard deviation) reaches a maximum of 0.009 Nm (at 80 million revolutions) compared with the limit of 0.12 Nm. The spectral composition of noise over the frequency band of interest is always well below the limits referred to white noise. Although not of direct importance to control stability, the 1 million revolution averaged torques remain in the range 0.0035 to 0.0102 Nm and there is no effect of speed upon average torque.